``` unison
thing = 3
foo.hello = 5 + thing
bar.hello = 5 + thing
hey = foo.hello
```

``` ucm

  Loading changes detected in scratch.u.

  I found and typechecked these definitions in scratch.u. If you
  do an `add` or `update`, here's how your codebase would
  change:
  
    ⍟ These new definitions are ok to `add`:
    
      bar.hello : Nat
      foo.hello : Nat
      hey       : Nat
      thing     : Nat

```
``` ucm
scratch/main> add

  ⍟ I've added these definitions:
  
    bar.hello : Nat
    foo.hello : Nat
    hey       : Nat
    thing     : Nat

```
``` unison
thing = 2
```

``` ucm

  Loading changes detected in scratch.u.

  I found and typechecked these definitions in scratch.u. If you
  do an `add` or `update`, here's how your codebase would
  change:
  
    ⍟ These names already exist. You can `update` them to your
      new definition:
    
      thing : Nat

```
``` ucm
scratch/main> update

  Okay, I'm searching the branch for code that needs to be
  updated...

  That's done. Now I'm making sure everything typechecks...

  Everything typechecks, so I'm saving the results...

  Done.

```